Fluid coupling fittings normally consist of two primary components or parts interconnectable in a sealed relationship to permit the flow of fluid therebetween. A wide variety of latching structure has been used to interconnect the parts or halves of fluid couplings, and the coupling and latch art has become highly developed to provide apparatus suitable for meeting the requirements of a variety of installations and circumstances.
A basic coupling fitting includes a female member adapted to sealingly receive a male member therein wherein relative axial displacement of the parts permits interconnection, and the connection is maintained by latch structure, the most popular being of a threaded nut type. It is also known to interconnect female and male coupling parts by latch structure which automatically functions merely by inserting the male part a predetermined axial distance into the female part. Such a push-in latch connection minimizes the operations necessary to interconnect the coupling parts and may be automatically functional requiring no additional action by the user than to insert the male part into the female part.
One type of push-in coupling connection which is known and desirable for its positive action and inexpensive manufacture utilizes resilient fingers mounted in the female part which engage with a shoulder formed on the male part upon the parts achieving a predetermined axial relationship. The resilient fingers are, initially, displaced radially outwardly by the shoulder as the male part is inserted into the female part, and after the fingers ride over the shoulder, they will snap into axial alignment with the shoulder to prevent withdrawal of the male part. Examples of such push-in fittings are shown in U.S. Pat. Nos. 3,933,378; 4,135,745; and in the assignee's application Ser. No. 706,442 filed Feb. 27, 1985, now U.S. Pat. No. 4,637,640.
Push-in connect fittings of the type shown in the above patents permit a concise, efficient and low-cost fitting to be manufactured, but as the resilient fingers are located within the female member, it is very difficult to uncouple such fittings, and most fittings of this type are intended to be irreversibly connectable, i.e. not disconnected after the initial interconnection of the parts has occurred. In those push-in fittings of the aforedescribed construction wherein it is intended to be able to uncouple the fitting parts a special tool must be used which is inserted into the female part for engagement with the fingers to displace the fingers from engagement with the male part shoulder and permit the parts to be separated.
It is an object of the invention to provide a push-in connection coupling fitting wherein the coupling parts are interconnected by resilient fingers and wherein finger release means are permanently mounted upon the coupling.
Another object of the invention is to provide a push-in connection for couplings utilizing resilient fingers wherein a permanent release sleeve is mounted upon the male fitting part and is axially displaceable thereon between finger locking and finger release positions.
A further object of the invention is to provide a push-in connection for couplings utilizing resilient fingers in the latch structure wherein a release sleeve is permanently mounted upon the male coupling part and the release sleeve is of such configuration, appearance, and operation as to discourage tampering and release of the finger latch mechanism.
An additional object of the invention is to provide a push-in connection for couplings utilizing resilient finger latch mechanisms wherein a finger release sleeve is permanently mounted upon the male part and is of such configuration as to be readily manually actuated between finger locking and finger release positions.
In the practice of the invention the male coupling part is inserted into the open end of the female part and an O-ring seal therebetween produces a fluid-tight relationship. Connection is achieved solely by relative axial part displacement and a push-in connection is produced.
Connection or latching is achieved by a plurality of resilient fingers mounted within the female part adjacent the open end thereof. The male part includes an annular shoulder which radially outwardly displaces the free end of the fingers as the male part is inserted into the female part passage and after sufficient relative axial displacement has occurred, the fingers will ride over the shoulder and "snap" into an axial abutting relationship with the shoulder preventing withdrawal of the male part.
The male part includes an annular release sleeve axially displaceable thereon having an inner end which is received within the female part and is capable of engaging the inside surfaces of the fingers. The outer end of the release sleeve extends from the female part and is exteriorly accessible. In one embodiment, the outer end of the release sleeve is of such a configuration as to not be recognizable as an operating component, while in another embodiment of the invention the outer end of the release sleeve is provided with a knob to facilitate manual actuation of the sleeve.
The release sleeve is easily axially displaced on the male member wherein the fingers will engage and slide the release sleeve to its inoperative finger locking position during connection of the coupling fitting parts, thereby preventing the release sleeve from inadvertently interfering with the positive connection of the parts achieved by the resilient fingers. However, when it is desired to disconnect the coupling parts an axial force is applied to the exterior portion of the release sleeve causing the sleeve to be axially displaced toward the fingers lifting the fingers from the male part shoulder. Once the fingers have cleared the shoulder the male part may be removed from the female part passage.
In one embodiment of the invention an abutment boss is defined on the male part which limits axial movement of the release sleeve, and the release sleeve is longitudinally slit in order to be temporarily deformed for insertion over the abutment boss to permit location of the release sleeve on the male part.
The permanent mounting of the finger release sleeve on the fitting permits push-in connection for couplings to be readily released, and as the release sleeve of the invention does not add bulk or significant costs to the coupling, its use provides a more versatile push-in connection for couplings than heretofore available.